This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 4 |
| 5 | 69 |
| 6 | 554 |
| 7 | 3100 |
| 8 | 13288 |
| 9 | 47492 |
| 10 | 147050 |
| 11 | 407568 |
| 12 | 1030912 |
| 13 | 2419025 |
| 14 | 5324684 |
| 15 | 11099416 |
| 16 | 22065120 |
| 17 | 42085344 |
| 18 | 77378556 |
| 19 | 137705904 |
| 20 | 237996060 |
| 21 | 400624581 |
| 22 | 658434694 |
| 23 | 1058839380 |
| 24 | 1669118984 |
| 25 | 2583424948 |
| 26 | 3931632406 |
| 27 | 5890783808 |
| 28 | 8699293304 |
| 29 | 12674960961 |